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Evolution of microstructure and properties of a novel Ni-based superalloy during stress relief annealing

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International journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1876-1889页

作者： lei jia Heng Cui Shufeng Yang Shaomin lü xingfei xie jinglong Qu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China State Key laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing GAONA Materials&Technology Co. Ltd.Beijing 100081China High-Temperature Materials Institute Central Iron and Steel Research InstituteBeijing 100081China

We discussed the decrease in residual stress,precipitation evolution,and mechanical properties of GH4151 alloy in different annealing temperatures,which were studied by the scanning electron microscope(SEM),high-resolution transmission electron microscopy(HRTEM),and electron backscatter diffraction(EBSD).The findings reveal that annealing processing has a significant impact on diminishing residual *** the annealing temperature rose from 950 to 1150℃,the majority of the residual stresses were relieved from 60.1 MPa down to 10.9 ***,the stress relaxation mechanism transitioned from being mainly controlled by dislocation slip to a combination of dislocation slip and grain boundary ***,the annealing treatment promotes the decomposition of the laves,accompanied by the precipitation ofμ-(Mo_(6)Co_(7))starting at 950℃ and reaching a maximum value at 1050℃.The tensile strength and plasticity of the annealing alloy at 1150℃ reached the maximum(1394 MPa,56.1%)which was 131%,200%fold than those of the as-cast alloy(1060 MPa,26.6%),but the oxidation process in the alloy was accelerated at 1150℃.The enhancement in durability and flexibility is primarily due to the dissolution of the brittle phase,along with the shape and dispersal of theγ′phase.

关键词： GH4151 alloy annealing treatment residual stress precipitation evolution strength mechanical properties

Surface engineering with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： xiting Zhang Chenyi Fang j Paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 l·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

ON THE MONTE CARlO SIMulATION OF NORMAl GRAIN GROWTH

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Acta Metallurgica Sinica(English letters) 2008年第4期21卷 282-288页

作者： Y.T. liu x.j. Guan x.M. Shen x.F. Ma l.j. Wang School of Materials Science and Engineering Shandong University Jinan 250061 China

The microstructures and their kinetics of normal grain growth are simulated using different Monte Carlo （MC） algorithms. Compared with the relative figures and the theoretical normal grain growth exponents of n =0.5, the effects of some factors of MC algorithm, i.e. the lattice types, the methods of selecting lattice sites, and the neighbors selection for energy calculations, on the simulation results of grain growth are studied. Two methods of regression were compared, and the three-parameter nonlinear regression is much more suitable for fitting the grain growth kinetics. A better model with appropriate factors included triangular lattice, the attempted site randomly selected, and the first and second nearest neighbors for energy calculations is obtained.

关键词： Grain growth Microstructure Monte Carlo method Computer simulation Grain growth kinetics Nonlinear regression

高、低核酸含量原核生物应对资源可利用性降低和原生动物选择性摄食的适应性策略

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中国科学：地球科学 2024年第6期54卷 1901-1913页

作者：胡晨余柳倩陈晓炜刘纪化张瑶 john BATT 肖喜林石蔷张锐骆庭伟焦念志徐大鹏厦门大学环境与生态学院厦门361102 近海海洋环境科学国家重点实验室厦门大学海洋与地球学院福建省海洋碳汇重点实验室厦门361102 joint lab for Ocean Research and Education(lORE)of Dalhousie university Canadaand Shandong University and Xiamen UniversityXiamen 361102China 香港科技大学(广州)地球与海洋大气科学学域广州510000 山东大学海洋研究院青岛266237 Department of Oceanography Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada 深圳大学高等研究院深圳518060 厦门大学碳中和创新研究中心厦门361102

原核生物在全球海洋生物地球化学循环中发挥重要作用,然而对它们不同生态亚群(即:高核酸(HNA)和低核酸(lNA)含量亚群)的丰度和代谢活性,以及它们的调控因素如何随着海洋环境条件的变化而变化,仍知之甚少.我们在117,000升的大体积培养体... 详细信息

原核生物在全球海洋生物地球化学循环中发挥重要作用,然而对它们不同生态亚群(即:高核酸(HNA)和低核酸(lNA)含量亚群)的丰度和代谢活性,以及它们的调控因素如何随着海洋环境条件的变化而变化,仍知之甚少.我们在117,000升的大体积培养体系中进行了73天的培养实验,深入研究HNA和lNA亚群对资源可利用性降低和原生动物选择性摄食随时间变化的动态响应.研究结果显示,当培养环境资源充足时, HNA亚群的代谢活性高于lNA亚群,但随着资源日益稀缺, HNA亚群代谢下降速度比lNA亚群快,从而使lNA亚群对原核生物活性的贡献稳步增加.与此同时,随着培养体系资源可利用性逐步降低,原生动物的摄食偏好从HNA亚群转向lNA亚群,使得lNA亚群对培养体系的碳流贡献增加.这些结果突显了lNA亚群在资源有限环境中的韧性,阐明了原生动物选择性摄食在资源条件变化时平衡不同亚群中的关键作用,并展示了在不同环境背景下原生动物和原核生物之间复杂的相互适应性.

关键词：微生物环大体积培养实验原核生物自上而下和自下而上调控作用碳流

Eutectic-reaction brazing of Al_(0.3)CoCrFeNi high-entropy alloys using Ni/Nb/Ni interlayers

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journal of Materials Science & Technology 2022年第26期121卷 245-255页

作者： Y.lei j.Sun x.G.Song M.x.Yang T.l.Yang j.Yin State Key laboratory of Advanced Welding and joining Harbin Institute of TechnologyHarbin 150001China Beijing Power Machinery Institute Beijing 100074China Sichuan Aerospace Changzheng Equipment Manufacturing Co. Ltd.Chengdu 610100China

In this study,a novel eutectic-reaction brazing of Al_(0.3)CoCrFeNi high-entropy alloys(HEAs)^(1)was investigated with a design of laminated Ni/Nb/Ni *** typical Al_(0.3)CoCrFeNi brazing seam consisted of proeutecticγ,the lamellar eutectic structure composed of face-centered cubic(FCC)phase(eutecticγ)and C14 laves,as well as a few amounts of Nb based solid solution.A high density of nanoscale ordered l1_(2)(γ)phase was precipitated withinγphase *** the brazing temperature raised from 1200 to 1320℃,the dissolution volume of Al_(0.3)CoCrFeNi alloy into Ni-Nb liquid was *** microstructure of the brazing seam changed from hypereutectic(blocky laves+γphase)to eutectic(laves+eutecticγ)to hypoeutectic structures(proeutecticγ+laves/γeutectic structure).The shear strength of joints was increased gradually due to the formation of eutectic lamellae and the cellular growth of proeutecticγ*** maximum shear strength of the joint brazed at 1320℃for 10 min was up to 592 MPa,reaching 95%of the base *** joint mainly ruptured in the soft proeutecticγphase in a ductile fracture mode.

关键词： High-entropy alloys Brazing Eutectic structure Shear strength

Dixon MRI对健康成年人背部伸肌年龄和性别相关变异的多参数定量评估

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国际医学放射学杂志 2024年第2期 247-248页

作者： P.Z.Chen Z.Zhou l.Sun x.K.Yu K.li j.li 王俊

摘要目的使用Dixon MRI研究健康成人年龄相关性背伸肌退变的性别差异，并分析肌肉定量参数与背肌力的关系。方法纳入105名健康受试者行腰椎Dixon MRI检查。量

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Harnessing naturally occurring mutations for T-cell therapy:a potential new avenue to enhance treatment efficacy

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1799-1801页

作者： Michael Hiltensperger jürgen Ruland Kilian Schober Mikrobiologisches Institut-Klinische Mikrobiologie Immunologie und HygieneFriedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany Institute of Clinical Chemistry and Pathobiochemistry School of MedicineTechnical University of MunichMunichGermany TranslaTuM Center for Translational Cancer ResearchTechnical University of MunichMunichGermany German Cancer Consortium(DKTK) HeidelbergGermany German Center for Infection Research(DZIF) partner site MunichMunichGermany FAu Profile Center Immunomedicine Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

In a recent study published in Nature,Garcia et *** a sophisticated approach to identify fitness-enhancing mutations for T cells that was inspired by cancer evolution.1 The identified CARD11-PIK3R3 gene fusion enhanced tumor rejection and persistence of engineered T cells in multiple tumor models and might have the potential to improve efficacy of adoptive T-cell therapies in cancer patients.

关键词： cancer potential

A simple modification to the classical SIR model to estimate the proportion of under-reported infections using case studies in flu and COVID-19

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Infectious Disease Modelling 2024年第4期9卷 1147-1162页

作者： leonid Kalachev jon Graham Erin l.landguth Mathematical Sciences University of MontanaMissoulaUSA Center for Population Health Research School of Public and Community Health SciencesUniversity of MontanaMissoulaUSA

Background:under-reporting and,thus,uncertainty around the true incidence of health events is common in all public health reporting *** the problem of underreporting is acknowledged in epidemiology,the guidance and methods available for assessing and correcting the resulting bias are ***:We aim to design a simple modification to the Susceptible e Infected e Removed(SIR)model for estimating the fraction or proportion of reported infection ***:The suggested modification involves rescaling of the classical SIR model producing its mathematically equivalent version with explicit dependence on the reporting parameter(true proportion of cases reported).We justify the rescaling using the phase plane analysis of the SIR model system and show how this rescaling parameter can be estimated from the data along with the other model ***:We demonstrate how the proposed method is cross-validated using simulated data with known disease cases and then apply it to two empirical reported data sets to estimate the fraction of reported cases in Missoula County,Montana,uSA,using:(1)flu data for 2016e2017 and(2)COVID-19 data for fall of ***:We establish with the simulated and COVID-19 data that when most of the disease cases are presumed reported,the value of the additional reporting parameter in the modified SIR model is close or equal to one,so that the original SIR model is appropriate for data ***,the flu example shows that when the reporting parameter is close to zero,the original SIR model is not accurately estimating the usual rate parameters,and the re-scaled SIR model should be *** research demonstrates the role of under-reporting of disease data and the importance of accounting for underreporting when modeling simulated,endemic,and pandemic disease *** reporting the“true”number of disease cases will have downstream impacts on predictions of disease dynamics.A simple parameter adjustment

关键词： Modeling of epidemics SIR type models flu and COVID-19 under-reporting parameter Proportion of reported disease cases

Improved Analytical Methods for Determination of Residues of Nitrapyrin and 6-Chloropicolinic Acid in Different Crop Matrices by liquid Chromatography-Tandem Mass Spectrometry

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journal of Agricultural Chemistry and Environment 2024年第3期13卷 263-281页

作者： Fabiola G. Zuno-Floriano Riza l. Reyes-Punongbayan Matt j. Hengel Department of Environmental Toxicology University of California Davis California USA

Novel analytical methods were developed for the determination of nitrapyrin and 6-chloropicolinic acid (6-CPA) residues in agricultural products. Nitrapyrin was extracted with hexane: toluene (1:1, v/v) and 6-CPA with 0.1 N sodium hydroxide (NaOH). For nitrapyrin, samples were cleaned with silica solid phase extraction (SPE) and for 6-CPA with C18 or carbon SPE. Analysis was performed by liquid chromatography-tandem mass spectroscopy (lC-MS/MS) with external calibration (0.010 to 0.0010 µg∙ml−1 for nitrapyrin and 0.0050 to 0.00025 µg∙ml−1 for 6-CPA). Recoveries for nitrapyrin and 6-CPA were 68% - 102% and 66% - 90%, respectively. Nitrapyrin was detected in celery and onion (−1) and 6-CPA in onion, mustard greens and lettuce (−1). lower level method validation (llMV) for nitrapyrin and 6-CPA was 0.020 µg∙g−1 and 0.050 µg∙g−1, respectively. The methods presented in this study are robust and were utilized for the registration of nitrapyrin on agricultural commodities in the united States.

关键词： Herbicide Agricultural Products External Calibration lC-MS/MS Registration